How to create a local administrator account on a domain network?

Question

Active Directory

Brad, probably, but here:
HELL is not mine, inherited from the previous administrator, who happily drove off to his village.
Subject. You need a user with access to the local administration of the machine. On the PC there are groups Administrators and Admin of the domain/scheme/etc. The administrators group is a domain administrator by default, has full access everywhere, incl. remotely and locally connect to the server. User Accounts in Control Panel is not working.

Answer 1

Well, create a user in AD and use the GPO to add his local administrators to the PC.
The task is quite trivial, there are many manuals on this topic. Here is the first link

Answer 2

Usually, in such cases, we simply give the domain account on a specific PC the status "Administrator", and not "User", I don't know what you have heaped up there.